Problem: Ashley ate 1 slice of cake. Umaima ate 2 slices. If Ashley ate $\dfrac{1}{5}$ of the cake, what fraction of the cake is remaining?
Answer: If 1 slice represents $\dfrac{1}{5}$ of the cake, there must have been a total of 5 slices. $\text{fraction of cake remaining} = \dfrac{\text{number of slices remaining}}{\text{number of slices total}}$ Together they ate 3 slices, which leaves 2 out of 5 slices remaining. There is $\dfrac{2}{5}$ of the cake remaining.